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<html lang="en">

<head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
</head>

<body>
    <script>
        let obj = {
            age: 22,
            address: "郑州",
            subject: "js",
            score: 99,
        };
                                //   JSON   是特殊的字符串 
        console.log(typeof obj);
        // 判断一个对象是否由该类生成。
        console.log(obj instanceof Object);

        // 1. 对象转化为 json 格式的字符串
        let result = JSON.stringify(obj);
        console.log(result);
        console.log(typeof result); // string

        console.log("--------------------------------");
        // 2. json 字符串转化为 对象
        let temp = JSON.parse(result);
        console.log(temp);
        console.log(typeof temp);  // 

        // 作业
        let arr = ["张飞", "吕布", "王一博", "易烊千玺"];
        let a = JSON.stringify(arr);
        let arr1 = JSON.parse(a)

        arr1.push('123');
        console.log(arr, arr1);
     </script>
</body>

</html>